Solid tires are used in various applications, including industrial applications such as lift trucks and similar vehicles. Solid tires are mounted on rims by pressing the tire onto the rim. Many of the solid tire rims have integral flanges on one side and removable rings that attach to the rim on the opposite side to retain the tire between the rings and the flange. Consequently, when mounting the solid tire, the rim is placed in a press with the flange located away from the forcing ram of the press. The tire is then fitted over the opposite side of the rim, and the press pushes the tire onto the rim by applying force to a “cage”. The cage includes a pair of flat rings spaced vertically by circumferentially-spaced supports extending between the two rings. One ring is contacted by the press, and the opposite ring engages the circumference of the solid tire. The available space inside the cage allows the operator to attach or remove the lock ring after the solid tire has been pressed, and held, onto the rim. Since the cage restricts the area within which the user can operate when attaching and removing the lock ring, and since these relatively small rings are extremely inelastic and difficult to handle, it is believed to be desirable to provide a tool that will assist in this operation.